Python列表：元素的修改、添加、刪除和排序

本文參考自《Python編程：從入門到實踐》，作者：Eric Matthes，譯者：袁國忠

操作	語法	舉例	結果
修改元素		motocycles = ['honda', 'yamaha', 'suzuki'] print (motocycles)   motocycles[0] = 'ducati' print (motocycles)	['honda', 'yamaha', 'suzuki']   ['ducati', 'yamaha', 'suzuki']
添加元素	在列表末尾添加元素：append()	motocycles = ['honda', 'yamaha', 'suzuki'] print (motocycles)   motocycles.append('ducati') print (motocycles)	['honda', 'yamaha', 'suzuki']   ['honda', 'yamaha', 'suzuki', 'ducati']
	在列表中插入元素：insert()	motocycles = ['honda', 'yamaha', 'suzuki'] print (motocycles)   motocycels.insert(0, 'ducati') print (motocycles)	['honda', 'yamaha', 'suzuki']   ['ducati', 'honda', 'yamaha', 'suzuki']
刪除元素	根據索引刪除：del，無法繼續使用	motocycles = ['honda', 'yamaha', 'suzuki'] print (motocycles)   del motocycles[1] print (motocycles)	['honda', 'yamaha', 'suzuki']   ['honda', 'suzuki']
	刪除末尾的元素：pop()，可以繼續使用 也可以根據索引刪除，如motocycles.pop(0)	motocycles = ['honda', 'yamaha', 'suzuki'] print (motocycles)   popped_motocycle = motocycles.pop() print (motocycles) print (popped_motocycle)	['honda', 'yamaha', 'suzuki']   ['honda', 'yamaha']   suzuki
	不知道索引時，根據值刪除元素：remove()，可以繼續使用	motocycles = ['honda', 'yamaha', 'suzuki'， 'ducati'] print (motocycles)   too_expensive = 'ducati' motocycles.remove(too_expensive) print (motocycles) print (too_expensive)	['honda', 'yamaha', 'suzuki', 'ducati']   ['honda', 'yamaha', 'suzuki']   ducati
元素排序	無返回值，徹底改變原值   永久性排序：sort()   反方向排序：sort(reverse = True)	cars = ['bmw', 'audi', 'toyota', 'subaru'] print (cars)   cars.sort() print (cars)   cars = ['bmw', 'audi', 'toyota', 'subaru'] cars.sort(reverse = True) print (cars)	['bmw', 'audi', 'toyota', 'subaru']   ['audi', 'bmw', 'subaru', 'toyota']   ['toyota', 'subaru', 'bmw', 'audi']
	有返回值，原值不會變   臨時性排序：sorted()   反方向排序：sorted(reverse = True)	cars = ['bmw', 'audi', 'toyota', 'subaru'] print (cars) print (sorted(cars)) print (cars)	['bmw', 'audi', 'toyota', 'subaru']   ['audi', 'bmw', 'subaru', 'toyota']   ['bmw', 'audi', 'toyota', 'subaru']
	無返回值，徹底改變原值   永久性反轉列表元素的排列順序：reverse()	cars = ['bmw', 'audi', 'toyota', 'subaru'] print (cars)   cars.reverse() print (cars)   cars.reverse() print (cars)	['bmw', 'audi', 'toyota', 'subaru']   ['subaru', 'toyota', 'audi', 'bmw']   ['bmw', 'audi', 'toyota', 'subaru']
	有返回值，不會改變原值   臨時性反轉列表的排列順序：[: : -1]	num = [1, 2, 3, 4]   num_new = num[::-1] print(num_new)   print(num)	[4, 3, 2, 1]   [1, 2, 3, 4]
合並列表	+或extend	A = [1, 2, 3, 4] B = [5, 6, 7, 8] A = A + B 或 A.extend(B)   print(A)	[1, 2, 3, 4, 5, 6, 7, 8]